This cool convertible car from the 80's contained the breathtaking amount of fourheadlight bricks in noble black.

Geometry of the headlight brick (measurement in "LDraw units")

Geometry of the headlight bricks

The geometry of headlight bricks is very interesting. Such a brick has two studs, one on top and one at the side. It also has two anti-studs, holes which will hold a stud from another brick. These anti-studs are located at the bottom (of course) and at the back of the brick, the squared cut-out is as big as a stud.

The numbers in the figure are shown in the so called "LDraw unit", a basic unit which is used in the virtual LDraw CAD system for LEGO elements.

The specific characteristic of a headlight brick doesn't fit a 100% to other LEGO elements. So there are rumours from time to time that this element will be discontinued in the future. But even LEGO designers want to avoid this and they use the headlight bricks in almost every LEGO set …

This construction uses Technic bricks with holes instead of headlight bricks or bricks with studs on the side. The space between these SNOT bricks is two studs, the "snoted" part is build by five 1x2 plates.